This commit is contained in:
mutouyun 2019-03-12 11:16:33 +08:00
parent eb1f15583e
commit 46051733bb
4 changed files with 85 additions and 91 deletions

View File

@ -18,12 +18,7 @@ class elem_array {
public:
using policy_t = Policy;
using cursor_t = decltype(std::declval<policy_t>().cursor());
#if __cplusplus >= 201703L
using elem_t = ipc::circ::elem_t<policy_t::template elem_param<DataSize>>;
#else /*__cplusplus < 201703L*/
using elem_t = ipc::circ::elem_t<policy_t::template elem_param<DataSize>::value>;
#endif/*__cplusplus < 201703L*/
using elem_t = typename policy_t::template elem_t<DataSize>;
enum : std::size_t {
data_size = DataSize,

View File

@ -13,28 +13,12 @@
namespace ipc {
namespace circ {
struct elem_head {
std::atomic<std::size_t> rc_ { 0 }; // read-counter
enum {
cache_line_size = 64
};
template <std::size_t DataSize>
struct elem_t {
elem_head head_;
byte_t data_[DataSize] {};
};
template <>
struct elem_t<0> {
elem_head head_;
};
template <std::size_t S>
elem_t<S>* elem_of(void* ptr) noexcept {
return reinterpret_cast<elem_t<S>*>(static_cast<byte_t*>(ptr) - sizeof(elem_head));
}
using u1_t = ipc::uint_t<8>;
using u2_t = ipc::uint_t<16>;
using u2_t = ipc::uint_t<32>;
constexpr u1_t index_of(u2_t c) noexcept {
return static_cast<u1_t>(c);

View File

@ -20,43 +20,37 @@ struct prod_cons_impl;
template <>
struct prod_cons_impl<wr<relat::single, relat::single, trans::unicast>> {
std::atomic<circ::u2_t> rd_; // read index
std::atomic<circ::u2_t> wt_; // write index
#if __cplusplus >= 201703L
template <std::size_t DataSize>
constexpr static std::size_t elem_param = DataSize - sizeof(circ::elem_head);
#else /*__cplusplus < 201703L*/
template <std::size_t DataSize>
struct elem_param {
enum : std::size_t {
value = DataSize - sizeof(circ::elem_head)
struct elem_t {
byte_t data_[DataSize] {};
};
};
#endif/*__cplusplus < 201703L*/
alignas(circ::cache_line_size) std::atomic<circ::u2_t> rd_; // read index
alignas(circ::cache_line_size) std::atomic<circ::u2_t> wt_; // write index
constexpr circ::u2_t cursor() const noexcept {
return 0;
}
template <typename E, typename F, typename EB>
bool push(E* /*elems*/, F&& f, EB* elem_start) {
template <typename W, typename F, template <std::size_t> class E, std::size_t DataSize>
bool push(W* /*wrapper*/, F&& f, E<DataSize>* elems) {
auto cur_wt = circ::index_of(wt_.load(std::memory_order_relaxed));
if (cur_wt == circ::index_of(rd_.load(std::memory_order_acquire) - 1)) {
return false; // full
}
std::forward<F>(f)(elem_start + cur_wt);
std::forward<F>(f)(&(elems[cur_wt].data_));
wt_.fetch_add(1, std::memory_order_release);
return true;
}
template <typename E, typename F, typename EB>
bool pop(E* /*elems*/, circ::u2_t& /*cur*/, F&& f, EB* elem_start) {
template <typename W, typename F, template <std::size_t> class E, std::size_t DataSize>
bool pop(W* /*wrapper*/, circ::u2_t& /*cur*/, F&& f, E<DataSize>* elems) {
auto cur_rd = circ::index_of(rd_.load(std::memory_order_relaxed));
if (cur_rd == circ::index_of(wt_.load(std::memory_order_acquire))) {
return false; // empty
}
std::forward<F>(f)(elem_start + cur_rd);
std::forward<F>(f)(&(elems[cur_rd].data_));
rd_.fetch_add(1, std::memory_order_release);
return true;
}
@ -66,16 +60,16 @@ template <>
struct prod_cons_impl<wr<relat::single, relat::multi , trans::unicast>>
: prod_cons_impl<wr<relat::single, relat::single, trans::unicast>> {
template <typename E, typename F, typename EB>
bool pop(E* /*elems*/, circ::u2_t& /*cur*/, F&& f, EB* elem_start) {
byte_t buff[sizeof(E)];
template <typename W, typename F, template <std::size_t> class E, std::size_t DataSize>
bool pop(W* /*wrapper*/, circ::u2_t& /*cur*/, F&& f, E<DataSize>* elems) {
byte_t buff[DataSize];
for (unsigned k = 0;;) {
auto cur_rd = rd_.load(std::memory_order_relaxed);
if (circ::index_of(cur_rd) ==
circ::index_of(wt_.load(std::memory_order_acquire))) {
return false; // empty
}
std::memcpy(buff, elem_start + circ::index_of(cur_rd), sizeof(buff));
std::memcpy(buff, &(elems[circ::index_of(cur_rd)].data_), sizeof(buff));
if (rd_.compare_exchange_weak(cur_rd, cur_rd + 1, std::memory_order_release)) {
std::forward<F>(f)(buff);
return true;
@ -89,12 +83,23 @@ template <>
struct prod_cons_impl<wr<relat::multi , relat::multi, trans::unicast>>
: prod_cons_impl<wr<relat::single, relat::multi, trans::unicast>> {
std::atomic<circ::u2_t> ct_; // commit index
enum : std::uint64_t {
invalid_index = (std::numeric_limits<std::uint64_t>::max)()
};
template <typename E, typename F, typename EB>
bool push(E* /*elems*/, F&& f, EB* elem_start) {
template <std::size_t DataSize>
struct elem_t {
byte_t data_[DataSize] {};
alignas(circ::cache_line_size) std::atomic<std::uint64_t> f_ct_ { invalid_index }; // commit flag
};
alignas(circ::cache_line_size) std::atomic<circ::u2_t> ct_; // commit index
alignas(circ::cache_line_size) std::atomic<unsigned > barrier_;
template <typename W, typename F, template <std::size_t> class E, std::size_t DataSize>
bool push(W* /*wrapper*/, F&& f, E<DataSize>* elems) {
circ::u2_t cur_ct, nxt_ct;
while (1) {
for (unsigned k = 0;;) {
cur_ct = ct_.load(std::memory_order_relaxed);
if (circ::index_of(nxt_ct = cur_ct + 1) ==
circ::index_of(rd_.load(std::memory_order_acquire))) {
@ -103,15 +108,28 @@ struct prod_cons_impl<wr<relat::multi , relat::multi, trans::unicast>>
if (ct_.compare_exchange_weak(cur_ct, nxt_ct, std::memory_order_release)) {
break;
}
std::this_thread::yield();
ipc::yield(k);
}
std::forward<F>(f)(elem_start + circ::index_of(cur_ct));
auto* el = elems + circ::index_of(cur_ct);
std::forward<F>(f)(&(el->data_));
// set flag & try update wt
el->f_ct_.store(cur_ct, std::memory_order_release);
while (1) {
auto exp_wt = cur_ct;
if (wt_.compare_exchange_weak(exp_wt, nxt_ct, std::memory_order_release)) {
break;
barrier_.exchange(0, std::memory_order_acq_rel);
auto cac_ct = el->f_ct_.load(std::memory_order_acquire);
if (cur_ct != wt_.load(std::memory_order_acquire)) {
return true;
}
std::this_thread::yield();
if (cac_ct != cur_ct) {
return true;
}
if (!el->f_ct_.compare_exchange_strong(cac_ct, invalid_index, std::memory_order_relaxed)) {
return true;
}
wt_.store(nxt_ct, std::memory_order_release);
cur_ct = nxt_ct;
nxt_ct = cur_ct + 1;
el = elems + circ::index_of(cur_ct);
}
return true;
}
@ -119,58 +137,53 @@ struct prod_cons_impl<wr<relat::multi , relat::multi, trans::unicast>>
template <>
struct prod_cons_impl<wr<relat::single, relat::multi, trans::broadcast>> {
std::atomic<circ::u2_t> wt_; // write index
#if __cplusplus >= 201703L
template <std::size_t DataSize>
constexpr static std::size_t elem_param = DataSize;
#else /*__cplusplus < 201703L*/
template <std::size_t DataSize>
struct elem_param { enum : std::size_t { value = DataSize }; };
#endif/*__cplusplus < 201703L*/
using rc_t = std::size_t;
/*
<Remarks> std::atomic<T> may not have value_type.
See: https://stackoverflow.com/questions/53648614/what-happened-to-stdatomicxvalue-type
*/
using rc_t = decltype(circ::elem_head::rc_.load());
template <std::size_t DataSize>
struct elem_t {
byte_t data_[DataSize] {};
alignas(circ::cache_line_size) std::atomic<rc_t> rc_ { 0 }; // read-counter
};
alignas(circ::cache_line_size) std::atomic<circ::u2_t> wt_; // write index
circ::u2_t cursor() const noexcept {
return wt_.load(std::memory_order_acquire);
}
template <typename E, typename F, typename EB>
bool push(E* elems, F&& f, EB* elem_start) {
auto conn_cnt = elems->conn_count(std::memory_order_relaxed);
template <typename W, typename F, template <std::size_t> class E, std::size_t DataSize>
bool push(W* wrapper, F&& f, E<DataSize>* elems) {
auto conn_cnt = wrapper->conn_count(std::memory_order_relaxed);
if (conn_cnt == 0) return false;
auto el = elem_start + circ::index_of(wt_.load(std::memory_order_acquire));
auto el = elems + circ::index_of(wt_.load(std::memory_order_acquire));
// check all consumers have finished reading this element
while (1) {
rc_t expected = 0;
if (el->head_.rc_.compare_exchange_weak(
if (el->rc_.compare_exchange_weak(
expected, static_cast<rc_t>(conn_cnt), std::memory_order_release)) {
break;
}
std::this_thread::yield();
conn_cnt = elems->conn_count(); // acquire
conn_cnt = wrapper->conn_count(); // acquire
if (conn_cnt == 0) return false;
}
std::forward<F>(f)(el->data_);
std::forward<F>(f)(&(el->data_));
wt_.fetch_add(1, std::memory_order_release);
return true;
}
template <typename E, typename F, typename EB>
bool pop(E* /*elems*/, circ::u2_t& cur, F&& f, EB* elem_start) {
template <typename W, typename F, template <std::size_t> class E, std::size_t DataSize>
bool pop(W* /*wrapper*/, circ::u2_t& cur, F&& f, E<DataSize>* elems) {
if (cur == cursor()) return false; // acquire
auto el = elem_start + circ::index_of(cur++);
std::forward<F>(f)(el->data_);
auto el = elems + circ::index_of(cur++);
std::forward<F>(f)(&(el->data_));
for (unsigned k = 0;;) {
rc_t cur_rc = el->head_.rc_.load(std::memory_order_acquire);
rc_t cur_rc = el->rc_.load(std::memory_order_acquire);
if (cur_rc == 0) {
return true;
}
if (el->head_.rc_.compare_exchange_weak(
if (el->rc_.compare_exchange_weak(
cur_rc, cur_rc - 1, std::memory_order_release)) {
return true;
}
@ -183,27 +196,27 @@ template <>
struct prod_cons_impl<wr<relat::multi , relat::multi, trans::broadcast>>
: prod_cons_impl<wr<relat::single, relat::multi, trans::broadcast>> {
std::atomic<circ::u2_t> ct_; // commit index
alignas(circ::cache_line_size) std::atomic<circ::u2_t> ct_; // commit index
template <typename E, typename F, typename EB>
bool push(E* elems, F&& f, EB* elem_start) {
auto conn_cnt = elems->conn_count(std::memory_order_relaxed);
template <typename W, typename F, template <std::size_t> class E, std::size_t DataSize>
bool push(W* wrapper, F&& f, E<DataSize>* elems) {
auto conn_cnt = wrapper->conn_count(std::memory_order_relaxed);
if (conn_cnt == 0) return false;
circ::u2_t cur_ct = ct_.fetch_add(1, std::memory_order_acquire),
nxt_ct = cur_ct + 1;
auto el = elem_start + circ::index_of(cur_ct);
auto el = elems + circ::index_of(cur_ct);
// check all consumers have finished reading this element
while (1) {
rc_t expected = 0;
if (el->head_.rc_.compare_exchange_weak(
if (el->rc_.compare_exchange_weak(
expected, static_cast<rc_t>(conn_cnt), std::memory_order_release)) {
break;
}
std::this_thread::yield();
conn_cnt = elems->conn_count(); // acquire
conn_cnt = wrapper->conn_count(); // acquire
if (conn_cnt == 0) return false;
}
std::forward<F>(f)(el->data_);
std::forward<F>(f)(&(el->data_));
while (1) {
auto exp_wt = cur_ct;
if (wt_.compare_exchange_weak(exp_wt, nxt_ct, std::memory_order_release)) {

View File

@ -213,7 +213,9 @@ struct test_cq<ipc::queue<T...>> {
}
void send(cn_t* /*cn*/, msg_t const & msg) {
cn_t{ ca_ }.push(msg);
while (!cn_t{ ca_ }.push(msg)) {
std::this_thread::yield();
}
}
};